#1 mop up v. to wash or wipe with or as if with a mop; "Mop the hallway now"; "He mopped her forehead with a towel". wn #2 mop up n. a concluding action. wn #3 mop up v. defeat thoroughly; "He mopped up the floor with his opponents". wn #4 mop up v. finish a task completely; "I finally got through this homework assignment". wn